@techreport{Vis97.sdf,
  author      = {Visser, Eelco},
  title       = {A Family of Syntax Definition Formalisms},
  year        = {1997},
  month       = {July},
  number      = {P9706},
  institution = {Programming Research Group, University of Amsterdam},
  urlpsgz     = {http://www.cs.uu.nl/people/visser/ftp/P9706.ps.gz},
  url         = {http://www.wins.uva.nl/pub/programming-research/reports/1997/P9706.ps.gz},
  pubcat      = {techreport},
  project     = {ASF+SDF and SDF},
  category    = {non-refereed},
}